Exploring
the tetrahedron with Cabri 3D, Adrian
Oldknow, November 2004. This is a preliminary report on discoveries
made, and results proved, by a small group of members of the Mathematical
Association (UK) – Michael Fox, Adrian Oldknow, John Rigby and
Sir Christopher Zeeman – in the course of one month.

Confirming
new results in 3D geometry with Autograph 3, Adrian
Oldknow, November 2004. In an accompanying report I have described
recent advances in the 3D geometry of a special kind of tetrahedron,
a 4-ball tetrahedron, which are generalisations of results about triangles,
circles and hyperbolae in plane geometry. In order to visualise
some of the results, and to have analytic confirmation (but not general
proof) for particular cases we need some analytic tools which are not
currently available in Cabri 3D. At the CabriWorld 2004
conference in Rome this September Douglas Butler talked about the new
version of his software Autograph 3 as being complementary to Cabri
3D. This note gives an example of this in practice.